This invention relates generally to nuclear reactors and more particularly, to the hydrogen water chemistry system in a boiling water nuclear reactor.
Boiling water nuclear reactors contain a plurality of systems to monitor the workings of the reactor. One important system is the hydrogen water chemistry system used to mitigate stress corrosion in the reactor pressure vessel. During the process of converting water to steam in the reactor, a portion of the water may be broken down into hydrogen and oxygen (2H.sub.2 O.fwdarw.2H.sub.2 +O.sub.2). The build-up of this dissolved hydrogen and oxygen is undesirable because it may contribute to the onset and acceleration of stress corrosion cracking of stainless steel piping and components in the reactor pressure vessel. The addition of hydrogen to the feed water causes a reduction in dissolved oxygen within the reactor internals and recirculation piping, and lowers the radiolytic production of hydrogen and oxygen in the vessel core region. To ensure that the hydrogen added to the feedwater is properly combined with oxygen to produce water, oxygen is added to the off-gas system upstream of the recombiners. To ensure stoichiometric balance of hydrogen and oxygen is maintained, hydrogen water chemistry systems typically include hydrogen and oxygen analyzers to monitor the recombiner exit. Process conditions at the sample location are saturated with temperatures in the range of about 130.degree. F. to 200.degree. F. Condensation from a gaseous sample at the elevated temperatures present in the system will destroy many types of oxygen and hydrogen gas analyzers.
It would be desirable to provide a system to remove moisture from a saturated gaseous sample to protect the sensors and electronic components of the oxygen and hydrogen gas analyzers used in a BWR hydrogen water chemistry system. It would further be desirable to provide a system to remove moisture from a saturated gaseous sample in a BWR that requires minimal external electrical, utility, or equipment support.